Scientific
Theories of the Near-Death Experience

The following are excerpts from Jean Ritchie's
excellent book
Death's
Door which is
unfortunately out-of-print. Here she describes all the various theories
explaining the near-death experience. It is important to
realize the fact that although the mechanism for the dying process in the
brain can be quantified, this by no means proves that NDEs are merely a vision produced by the brain which ends upon permanent brain
death. Science is unable to prove this because of the
large
amount of circumstantial evidence that consciousness can exist far
removed from the body. In the same vein, science cannot prove that
consciousness can survive death; however, research is underway right now
that may provide scientific evidence that consciousness can exist outside
of the body. Many people, such as myself, believe it is only a matter of
time. NDE researchers do not have to prove anything. The circumstantial
evidence is in their favor. But science has a lot of explaining to do if
tries to claim that consciousness does not survive death.

A good analogy of one current
theory of consciousness assumes that consciousness is not localized in the
skull. Assuming consciousness is like a television signal that exists in the air
waves and is being processed by a television set (the brain) to
produce images on the screen (brain chemistry) representing a
television program (a near-death experience). Using this analogy,
current scientific theories claim that the near-death experience is a
product of the television set. In other words, the television program is a
product of the television set. Using the analogy, this would be false
because it is the television signal working with the television that
produces the television program. Some scientific claims state that death
is the end of consciousness - like shutting of the television set is the
end of the television signal in the air waves. Using this analogy, you can
see that such a statement is false. Shutting off the television does not
affect the television signal in the air waves. Some of the top
consciousness researchers believe this analogy fits, that is,
consciousness is like the television signals in the air waves and that
death is not the end of consciousness. Shutting off the television set
does not affect the signal in the air waves.

The following are the
scientific theories concerning the phenomenon of the
near-death experience.

This theory is one that has
been popularized by Dr., Susan Blackmore in her book
Dying
To Live. One of the greatest strengths of the afterlife theory and the argument
that NDEs are real is also one of its greatest weaknesses. The
fact that all those who had NDEs follow the same path toward the light,
going through similar stages on the way, makes a powerful case for the whole thing being a
profound spiritual journey to an afterlife where everyone, from all ages and cultures, is
welcome. But that same case, the "sameness" evidence, is also a
fundamental part of the argument that NDEs are not real experiences,
not spiritual voyages, but a function of the dying brain. All brains, regardless of
where in the world they come from, die in the same way, say the skeptics. And that
is why all NDEs have essential core elements which are the same.
It is not because the dying person is traveling toward a beautiful afterlife, but because
the neurotransmitters in the brain are shutting down and creating the same lovely
illusions for all who are near-death.

But why? Why should the dying brain do
this, if it is just a highly sophisticated lump of tissue? That question is one of
the most fundamental questions in the whole of human thinking. It boils down to
asking, are we individuals with "personalities" and "souls" and
"minds" that are exclusive to us? Or are we simply bodies controlled
by very clever computers, or brains, each of which works a little differently from the
rest, thus making each of us unique, just as an Apple computer is different from an IBM,
although there are far more similarities between them than there are differences?

Scientists and researchers are divided.
There are some who want to reduce NDEs to nothing more than a series
of brain reactions. Others, who accept the realness and validity of NDEs, are nonetheless quite happy to see it put into a scientific
context. In other words, they are not frightened of researching the experience
rigorously, of finding out everything that we possibly can about it, perhaps even being
able to explain aspects of it. But they can happily let that scientific aspect sit
alongside the deeply personal, life-enhancing evidence of those who have actually been
there.

There are very few people around, even among
the skeptics, who would deny that people have NDEs, and that they are deeply affected by
them because so many obviously sane and well-balanced people have now come forward and talked
about what happened to them. What they do dispute is what causes an NDE and what it means. There are two main strands of research: one takes the
psychological approach, which looks for reasons for human beings to behave the way they
do, and to think and possibly to hallucinate the way they do. The other is the
straightforward physiological approach, which is searching for that part of the brain
which malfunctions and causes an NDE. Increasingly, as in all brain research,
not just that connected with NDEs, the two approaches overlap.

The ruthless, depersonalized argument - that
an NDE is just the result of the brain beginning to die - is not
acceptable to the vast majority of people who had an NDE. To reduce what was a
profound and transforming experience to nothing more than a set of neurotransmitters going
on the blink is a bit like seeing Michelangelo's statue of David as nothing more than
several tons of marble.

If there is no afterlife, and
NDEs are just the last throw of a fevered and dying brain, why does it bother?
If everything, including the soul and personality, is going to dust and ashes, why does
the brain lay on this last wonderful floor show for people near-death, or facing actual
death, who relax into peacefulness and describe their wonderful visions?

If NDEs are just a
hallucination, why do a great many people report being told, "Your mission has not
been completed," or, "The time for your death is not yet," during their
NDE? If NDEs are just hallucinations, how can so many people be told the
same thing in their hallucinations? Isn't it odd that so many people are being told the
same thing? Are they all hallucinating identical responses? For many people,
it is easier to believe that NDEs are a real afterlife experience and not
mass hallucination.

One theory is that it is a deliberate ploy of the human race to help those behind adapt
better to the inevitable ending of their lives. Darwin's simple theory of the
survival of the fittest holds that every species is struggling to increase its hold on
this planet and guarantee the survival of its descendants. That is our greatest
primary urge. Other animals help their peers to survive: the dying elephant,
for example, trails away into the bush so that he does not slow down the herd. Are
the dying just "helping the herd" by putting out propaganda that death does
not contain a sting? But this theory does not explain why NDEs are
erratic, or why we shunted down an evolutionary sidetrack for years by making them
something that people were reluctant to talk about. After all, in Darwinian terms,
humans are the most highly evolved intellectual life forms on Earth.

Some scientists from the camp that believes that NDEs are one day going to
be explained by brain functions have suggested that the dying secrete endorphins, hormones
which act on the central nervous system to suppress pain and which are known to create the
"runner's high", which happens when long-distance runners go through a pain
barrier and find themselves running with ease and without tiredness, and with a feeling of
elation. But endorphins are not hallucinogens and cannot re-create a state
similar to NDEs, so although they may be involved in the process as a painkiller, they are not
responsible for the whole experience.

Research on neurotransmitter receptors is
highly complex and, in terms of our understanding of the functioning of the brain, in its
infancy. It is known that a powerful anesthetic called
ketamine can produce many of
the features of an NDE, particularly the out-of-body element, and one theory is that a
ketamine-like substance may be released by the body at the time of an NDE, and may attach
itself to certain neurotransmitter receptors and be responsible for producing the whole
NDE by blocking those receptors.

A psychology professor named
Dr.
Ronald Siegel
from UCLA rejects the spiritual and mystical importance of NDEs. He claims to
have reproduced NDEs in his laboratory by giving LSD to volunteers, but,
other researchers say that although drug-induced hallucinations may have some resemblance
to NDEs, they are not the same. For one thing, drug induced hallucinations often
evoke fearful and paranoid experiences which are not generally found in NDEs.
Drug induced hallucinations distort reality while NDEs have been
described as "hyper-reality."

Some features of the NDE are known to occur in a type of
epilepsy
associated with damage to the temporal lobe of the brain, and researchers have found that
by electrically stimulating this lobe they can mimic some elements of NDEs, such as
leaving oneself behind, and the sense of life memories flashing past, although this is
actually a common feature of NDEs.
They believe that the stress of being
near-death, or thinking that you are near-death, may in some way cause the stimulation of
this lobe. There is some evidence to support this theory in the lower numbers of
NDEs reported by people who suffer strokes which affect this part of the
brain, or have tumors in this area. But there is also a case against: the characteristic
emotions that result from temporal lobe stimulation are fear, sadness, and loneliness, not
the calm and love of an NDE. Also, scientists may be simply discovering the
mechanism connected with the mind/body separation thought by some to occur at death.
Because a chemical mechanism is present in the brain, this does not mea NDEs are strictly chemical reactions. Science may only be describing the
aspect of dying that deals with the brain.

Other possible explanations are a
lack of oxygen in the
brain, or too much carbon
dioxide. But these would not explain why some patients are able to give full and
cogent reports of things that went on around them during their NDE. Cardiologist
Dr. Michael Sabom has reported one patient who, while having an NDE, watched his doctor
perform a blood test that revealed both high oxygen and low carbon dioxide.
Comparisons between NDEs and hallucinations produced by an
oxygen-starved brain show that the latter are chaotic and much more similar to
psychotic
hallucinations. Confusion, disorientation, and fear are the typical
characteristics, compared with the tranquility, calm, and sense of order of
an NDE.
There are some features in common: a sense of well-being and power, and themes of
death and dying. But people who have experienced both at different times say that
there is an unmistakable difference.

Hallucinations, whether deliberately
drug-induced, the result of medication, or caused by oxygen deprivation, almost always
take place while the subject is awake and conscious, whereas NDEs happen
during unconsciousness, sometimes when the subject is so close to death that no record of
brain activity is recorded on an electroencephalograph, the machine that monitors
brain waves. Also, the medical conditions that take subjects to the brink of death,
and to having an NDE, do not necessarily include oxygen-deprivation, or any
medication. This is particularly true of accident victims. NDEs appear to occur at the moment when the threat of death occurs, not necessarily
at the time, maybe hours later, when death is close enough to be starving the brain of
oxygen.

The first modern attempt to explain NDEs in psychological terms was made
in 1930 by a psychologist who argued that people faced with an unpleasant reality of death
and illness attempt to replace it with pleasurable fantasies to protect
themselves. They "depersonalize," removing themselves from themselves -
the floating away from their own bodies that experiencers report having. It is a theory that is
still sometimes put forward, but it can be countered by the fact that some typical
features of an NDE just do not fit into the
depersonalization mode, such
as the strong spiritual and mystical feelings, and the increased alertness and awareness.

Another popular theory is that NDEs have nothing to do with death at
all, but are memories of
birth. A baby being born leaves the womb to travel down a
tunnel towards a light, and what waits for it in the light is usually a great deal of
love and warmth. What happens at the point of death is only a stored memory of what
happened when life began. Yet again there are a lot of points that don't match:
a baby being born does not exactly float at high speed down a tunnel, but is buffeted
along with difficulty by its mother's contractions. And how does this model explain
the meeting with friends and relatives who have died? The "Being of Light"
is supposed to be the midwife or the doctor who rules the delivery room - but many babies
are born without a midwife or doctor present, or perhaps with many people present.
On a purely practical level, a baby's nervous system is not sufficiently developed to
allow it to assimilate and store memories of the birth process.

Those who argue this theory say that the
feelings of peace and bliss are a memory of the peace of the womb when all physical needs
were met by the mother and there were no stresses and strains. Why should this be
any more likely than the feelings of peace and bliss are relief from the pain of illness
and injury at the point of death? However, being born is often not a pleasant
experience for babies which leaves them crying as if in agony. In contrast,
NDEs are more often described as the most pleasurable experience a person
can have. The birth process is not pleasant.

Dr.
Kenneth
Ring, one of the most respected
near-death researchers who has done much work of putting the subject of NDEs on
the academic map, has this to say about the afterlife theory:

"Any adequate neurological explanation would have to be
capable of showing how the entire complex of phenomena associated with the core
experience [that is, the out-of-body state, paranormal knowledge, the tunnel, the
golden light, the voice or presence, the appearance of deceased relatives, beautiful
vistas, and so forth] would be expected to occur in subjectively authentic fashion as a
consequence of specific neurological events triggered by the approach of
death ... I am tempted to argue that the burden of proof has now shifted to
those who wish to explain NDEs in this way." (Dr.
Kenneth
Ring)

Those sentences are a couple of
complicated sentences,
but what Ken Ring is saying is that there are so many consistent features of
NDEs that it is going to be very difficult to find a good explanation for them in
terms of the physical working of the brain. And, he believes, that the evidence is so strong for
them that sympathetic researchers should no longer feel that the burden is on
to them to prove that
they happen, but rather, for the skeptics to prove that they don't.

"There is no human experience of any description that can't simply be
reduced to a biological process, but that in no way offsets the meaning those experiences
have for us - whether it's falling in love, or grieving, or having a
baby." Or coming close to death and having a transcendental experience.
(Nancy
Evans Bush)

There is a "mountain" of
scientific evidence suggesting consciousness can survive bodily death.
Some of this evidence has been verified through NDEs
involving "veridical
perception." Some of the evidence is spontaneous and
circumstantial and of the kind that would stand up in a court of law. Some
researchers have pointed out how science has not even been
able to quantify consciousness, let alone trying to quantify
the NDE. Scientists certainly lack the necessary tools to
fully quantify and understand the nature of consciousness.
The problem facing scientists in this matter is how
consciousness can arise from a lump of goo (the brain) or
how a conglomeration of atoms and molecules can produce the
mind. Perhaps someday when science has discovered the true
nature of consciousness, we may then be on the road to
finding conclusive scientific evidence of an afterlife.